July 16, 2012

Watching TV Leads To Weight Gain And Physical Weakness

Watching too much TV is generally considered unhealthy by many experts, and that could be no more true than in a new study published in BioMed Central℠s ℠International Journal of Behavioral Nutrition and Physical Activity´ (IJBNPA) that has found the more hours young children spend in front of the screen, the more they are adding to their waist line as they continue to grow.

Children under the age of two should not spend any more than two hours per day watching TV, recommends the American Academy of Pediatrics. However, growing evidence suggests that parents may be relying more on TV as an “electronic babysitter,” a consequence that could be detrimental to their children´s´ physical well-being as they age.

According to researchers, led by Dr. Caroline Fitzpatrick from New York University and senior author Dr. Linda Pagani from the University of Montreal, two- to four-year-olds who spend too much time watching TV are inadvertently contributing to their waist size by the end of the fourth grade, and perhaps hindering his or her ability to play in sports.

“We already knew that there is an association between preschool television exposure and the body fat of fourth grade children, but this is the first study to describe more precisely what that association represents,” said Pagani.

For their study, Pagani and Fitzpatrick used participants from the Quebec Longitudinal Study of Child Development, and assessed parental reports of the number of hours their kids spent watching TV per week at 2-and-half-years (29 months) and 4-and-a-half years old (53 months).

“Trained examiners took waist measurements and administered the standing long jump test to measure child muscular fitness. We found, for example that each weekly hour of TV at 29 months of age corresponds to a decrease of about a third of a centimeter in the distance a child is able to jump,” explained Pagani.

Not only did the standing long jump test reveal important clues about muscular fitness, it also revealed an individual´s athletic ability, as sports such as football, skating, and basketball require the "explosive leg strength" measured by the test.

The team found that for each hour of TV viewing per week at 29 months, a 0.14 inch decrease in the standing long jump test was seen, indicating loss of muscle strength. An extra hour´s increase in weekly TV exposure correlated to an extra 0.11 inch reduction in performance in the test.

The team also found that waist circumference at fourth grade increased by 0.01 inches for every hour of TV watched between the ages of 29 and 53 months. That, in turn, corresponded to a 0.16 inch increase in waist size by age 10, or a 0.29 inch increase for those who watched more than 18 hours of TV per week.

“TV is a modifiable lifestyle factor, and people need to be aware that toddler viewing habits may contribute to subsequent physical health.” warned Fitzpatrick. “Further research will help to determine whether amount of TV exposure is linked to any additional child health indicators, as well as cardiovascular health.”

While the team stresses that further research is needed to establish that TV exposure is the direct cause of the health issues observed, this study should encourage authorities to develop policies targeting environmental factors associated with childhood obesity.

“The bottom line is that watching too much television — beyond the recommended amounts — is not good,” Pagani concluded.

“These findings support clinical suspicions that more screen time in general contributes to the rise in excess weight in our population, thus providing essential clues for effective approaches to its eradication,” the American Academy of Pediatrics said.